Railway signaling



1930- T. J. OMEARA RAILWAY SIGNALING Filed Jan. 16, 1950 of said si apparatus will be restored to the conditions" inwhich'they are shown in the drawing.

-. "Iwill-now assume that after having energized the take-siding signal S the despatcher desires to withdraw the take-siding indication. To do this, he Will operate his code key K thereby causing selector D to respond in such manner as to momentarily close its contact 7. a While contact 7 of this selector is closed, relay C will be energized by a circuit which passes from battery 4, through the windin of relayC, winding'h "and contact 7 ofse ector D and switch contact 3 to battery 4. The closing of relay C willop'en the stlck circuit forrelay B at back contact 14, so that relay B willbecome deenergized.' During the brief interval of time between the closingof contact 7 of selector D and the release of relay B, current will flaw from battery 4, through the buzzer H, frdnt'point or contact 9 of relay B, winding G'and contact 7 of selector D and contact 3 to battery 4. The eriodically interrupted current which then ows in theanswer-back winding 6 'willinduc e an alternating current in winding 5 of selector D ,and the latter current will'cause a buzz in the-[telephone P. Thebeginning of this buzz will indicate to the despatcher that the selector D has responded, and the cessation ofthe buzz will indicate'that relay B has released. The buzz due to the operation of the cancelling selec tor I) Willllast slightly longer than the buzz due to the take siding selector I), because relayB will require a longer time to release than'it does to ick up.

Although I ave herein shown and de- 'scribed'only one form of apparatus embodyin g my invention, it is understood' 'that various changes and inodifications maybe made therein within the scope of the appended' claims without departing from'the spirit and sec eof my invention.

aving thus described my invention, what I claim is: a

1. In combination, a railway trackprovidedwith a switch leadinginto a siding, said track bein divided by insulated joints to form'a trac li se'ction in the rear of said switch,

a track circuit including a track'relay forsaid section, a' take-siding signal located'in the rear of said switch and within the limits 0f said track Section, a relay A for the control a1, a take-sidingrelay B,'a cir-' cuit "forrelay A controlled by a front contact of relay B and a back contact of said track relay, a take-siding selector and a ca'ncelling selector, each having a normally open contact, means controlled from a distant point for operating either of said selectors to momentarily close the associated contact, a pick-up circuit for relay B including the contact of said take-siding selector and a normally closed contact which opens when said switch is opened, a normally open relay C, a circuit for relay C including the contact of said cancelling selector and said switch contact, a stick circuit for said relay B includin a front contact thereof and a back contact 0? relay C as well as said switch contact, an answer-back winding on each of said selectors,

a buzzer, a circuit for the answer-back winding on the take-siding selector including said buzzer and a back contact of said relay B, and'a circuit for the answer-back winding on said cancelling selector including said buzzer and a front contact of said relay B.

2. In combination, a railway track provided with a switch leading into a siding,said

track bein divi'ded'by insulated joints to form atrac section in therear ofsaid'switch,

a track circuit includinv a track relayfor said section, a t'ake-siding signal located in the rear of said switch and within the limits of said track section a relay A for the control of saidsignal, a ftake-si'ding relay B, a circuit {for relay A controlled by a front contact of relay B and a back contact of said track relay,

' a t'ake sidlngselector and a cancelling sefor relay C includingthe contact of said cancelling selector and said switch contact,and a stick circuit for said relay B includin a front contact thereof and aback contact 0 relay C as well as said switch contact.

3. In combination, a railway track provided with a switch leading into a siding, a take-siding si nal located in the rear of said switch, a relay for the control of said signal, a take-siding selector and a cancel-. ling selector, each having a'normall open contact,means controlled from a istant point for operating either of said selectors to -momentari p y close the associated contact, a pick-'upicircuit for relay B including the contact of said take-sidin selector and a nor: mally Contact w ich opens when said switchis' opened,a'normally open relay C, a

circuit 'for relay Cfinchidin the contact of saidcancelling selector and said-switch contact, a'stickcircuit for'said relay Bincludin a front contact thereof and a back contact 0 relay C as well as said switch contact, an'ansWer-back Wlndln'gOn each of said selectors, a buzzer, a circuit for the answer-back winding on the take-siding selector including said buzzer and a back contact of said relay B, and a circuit forthe answer-back winding on said cancelling selector including'said buzzer and a front contact of said relay B.

4. In combination, a railway track provided with a switch leading into a siding, a take-siding signal located in the rear of said switch, arelayB for the control of said signal, a take-siding selector D and a cancelling selector D each having a normally open contact, means controlled from a distant point for opcrating either of said selectors to a momentarily close the associated contact, a

pickup circuit for relay B including the corn tact of said take-siding selector and a normally closed contact which opens when said switch is opened,,a normally open relay C, a

circuit forrelay C including the contact of i said cancelling selector and said switch contact, and a stick circuit for said relay B ineluding a front contact thereof and a back well as said switch concontact of relay G as tact.

, oMAs J. OMEARA.

In testimony whereof I afiix my signature. 

